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781.
文化对机组资源管理的影响   总被引:1,自引:0,他引:1  
针对国内民航机组资源管理(CRM)及训练中忽视文化的作用和影响的现状,在调研和分析国外CRM与文化影响的基础上,笔者结合国内民航的运行特点,总结、分析了民族文化、组织文化,以及职业文化对机组协作与配合,CRM训练等方面的积极与消极影响,提出中国民航应根据自身的文化特点调整CRM训练的内容和实施方式,并应从3个层面采取措施来提高CRM及其训练的效果,即航空公司CRM训练的设计、实施与评估;飞机制造商在进行驾驶舱人-机界面设计,以及政府部门在对航空器进行适航审定时,应充分识别不同文化的差异、在强化各种文化类型积极影响的同时,努力降低或消除其消极影响。  相似文献   
782.
高层建筑救火模型的研究   总被引:1,自引:0,他引:1  
在分析我国目前高层建筑救火费用(救火消防车数和消防队员数)的基础上,提出运用优化数学的思路,建立高层建筑救火模型。首先,确定高层建筑救火费用的目标函数、约束条件、策略,将目标函数写成约束条件和策略的函数;然后,根据高层建筑火灾的特点,提出建立模型的8个假设条件,从而建立一个高层建筑救火数学模型,运用高等数学微积分的有关知识对数学模型进行求解与分析,从而达到高层建筑救火费用最低的目的。最后,以实例论证了该数学模型在高层建筑救火中的应用效果,同时为高层建筑救火提供理论上、方法上的指导。  相似文献   
783.
ObjectivesAn increasing number of complaints related to time spent in artificially ventilated buildings have been progressively reported and attributed, at least in part, to physical and chemical exposures in the office environment. The objective of this research was to investigate the association between the prevalence of work-related symptoms and the indoor air quality, comparing a sealed office building with a naturally ventilated one, considering, specially, the indoor concentration of TPM, TVOCs and the main individual VOCs.MethodsA cross-sectional study was performed to compare the prevalence of sick building syndrome (SBS) symptoms among 1736 office workers of a sealed office building and 950 of a non-sealed one, both in Rio de Janeiro's downtown. The prevalence of symptoms was obtained by a SBS standardized questionnaire. The IAQ of the buildings was evaluated through specific methods, to determine the temperature, humidity, particulate matter and volatile organic compound (VOC) concentrations.ResultsUpper airways and ophthalmic symptoms, tiredness and headache were highly prevalent in both buildings. Some symptoms were more prevalent in the sealed building: “eye dryness” 33.3% and 27.1% (p: 0.01); “runny nose” 37.3% and 31.3% (p: 0.03); “dry throat” 42% and 36% (p: 0.02); and “lethargy” 58.5% and 50.5% (p: 0.03) respectively. However, relative humidity and indoor total particulate matter (TPM) concentration as well as total volatile organic compounds (TVOCs) were paradoxically greater in the non-sealed building, in which aromatic compounds had higher concentration, especially benzene. The analysis between measured exposure levels and resulting symptoms showed no association among its prevalence and TPM, TVOCs, benzene or toluene concentration in none of the buildings.ConclusionsOther disregarded factors, like undetected VOCs, mites, molds and endotoxin concentrations, may be associated to the greater prevalence of symptoms in the sealed building.  相似文献   
784.
This research is a three-dimensional investigation about the aerodynamic interaction between the wind flow and a single high-rise building. In order to find location(s) with high potential of velocity around the building, a wide variety of wind speeds ranging from 2 to 10 m/s is studied. On the other hand, a high-rise building with the ratio of height to width of H/W = 3 is considered. Computations are performed numerically by means of the finite volume approach. Several results are obtained in the present numerical study. For example, it is found that due to wind-structure vertical interaction, locations with enhanced velocities are developed on the building roof in which the rate of this enhancement increases with increasing the wind speed. In addition, over the building, “lines C and D” are realized as the best locations having high power potentials and low turbulence intensities. In addition, lateral wind-structure interaction revealed that for all wind speeds, location of L/W = 0.5 is the best for the small wind turbine installation.  相似文献   
785.
The adoption and enforcement of building codes is considered the most effective tool in safeguarding lives and property against earthquakes. There would appear to be a vital regulatory role for government in the enforcement of building codes, but this is somewhat at odds with the neoliberal agenda of ‘rolling back the state’. This paper explores constraints to the implementation of building codes in the context of changing roles and responsibilities of local authorities in Bihar in India. In-depth interviews were conducted with key stakeholders across major urban centres in north Bihar. Some factors, such as: code complexity; competition between the public and private sectors for qualified personnel; and low public risk perception were found to be less significant in Bihar than has been noted elsewhere, while other factors such as: the cost of earthquake-resistant measures; political interests; corrupt practices; and lack of government capacity were important. Additional factors were also revealed by the research, some of which are exacerbated by the neoliberal climate of urban governance. While the recent 2014 byelaws represent an improvement in the system and a degree of re-regulation, ambiguities create opportunities for failures arising from ‘normalised irresponsibility’.  相似文献   
786.
The purpose of this paper is to increase understanding of the dynamics of knowledge production in the context of large-scale environmental projects causing local conflict. In particular, the paper analyses the discourse coalitions that formed around an artificial groundwater recharge project for the Turku Region in Finland. The material for this study consists of over 400 articles and opinion pieces which were collected from local and regional newspapers between 1999 and 2010. The articles were analysed by using Hajer's [1995. The politics of environmental discourse. Ecological modernisation and the policy process. Oxford, UK: Clarendon] discursive framework, and the analysis was complemented with the concept of knowledge coalition by Van Buuren and Edelenbos [2004. Conflicting knowledge. Why is joint knowledge production such a problem? Science and Public Policy, 31 (4), 289–299]. Results of the study indicate that knowledge coalitions were formed among the researchers, lay residents, and policy-makers, and they all utilised similar expertise-based factual arguments to support their cause. Thus, the paper participates in the academic discussion on the use and interpretation of expert knowledge in environmental policy-making by reshaping the division between experts and lay residents.  相似文献   
787.
There is a need for specific knowledge of what people can do to mitigate harmful water conflicts. This need is evident in the rural dry tropics of Central America where people face climate change impacts, inefficient water management, and social tension. To address this need, we investigated why some local water conflicts escalated to violence and why other potential conflicts were avoided in Guanacaste Province, Costa Rica. We used interviews, focus groups, and a stakeholder workshop to analyse five cases. We found that violent actions only occurred when rural groups opposed government agencies in settings without mediating leadership. With one exception in a circumstance aggravated over many years, water users did not take violent action against competing water users. Distrust, which has been formed by legacies of ineffective rural stakeholder engagement, diminished the credibility of water-related information used in decision processes and thus prolonged conflicts. Active community-based groups respected by both rural constituencies and government agencies helped some people avoid difficult conflicts. Self-organised groups in other areas struggled to address disputes in settings with contested property rights, high socio-economic inequality, and low human capital. Using insights from Guanacaste, we outline practical conflict mitigation strategies fitted to a range of local water governance contexts found in rural Central America. Results suggest the need for incorporating certain types of peace-building processes in water management and development. The study provides a foundation for policy-makers, water managers, and other stakeholders to more effectively manage water disputes and avoid harmful conflicts in challenging regions.  相似文献   
788.
根据性能设计的要求,高层建筑的抗风设计需要考虑人员舒适性要求。本文提出了用于结构顺风向风振响应分析的广义脉冲响应函数法,用来计算随机激励和结构响应之间的传递函数,这样就可以计算高层建筑结构在风荷载作用下的动力响应特性,并用动力可靠度计算结构在脉动风荷载作用下的舒适度失效概率。  相似文献   
789.
石棉尾矿水热合成建筑材料的研究   总被引:9,自引:0,他引:9  
对利用石棉尾矿水热合成建筑材料进行了研究。结果表明,石棉尾矿预处理的最佳温度为950℃,石棉尾矿90%,MA和NB各5%材料的性能较好。  相似文献   
790.
滇池富营养化水体新型除藻材料的试验研究   总被引:7,自引:1,他引:6  
通过实验室小试 (2 0L)和滇池水体围栏扩大试验 (30 0m2 ) ,研究新型轻质除藻材料对滇池湖水中藻类的除藻及净化作用。小试结果表明 ,该除藻材料放入滇池水样实验 2 6d后 ,水质明显好转 ,藻类去除率可达 98% ,COD、TN及TP的去除率达到 38%~ 62 %。滇池湖边 30 0m2 水面围栏扩大试验结果显示 ,除藻材料放入试验区水体 1 0d后 ,水体中藻类含量明显减少 ,水体透光率从 55 %增加到 80 % ,水质状况也有很大改善。研究表明 ,该除藻材料是一种具有研究和应用价值的新型水体除藻材料。  相似文献   
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